Help figuring out if I can build a yurt in Brooklyn

[hierony]

Thank you Bob! I've lurked this forum quite a bit looking for people's snow load experiences--I was trying to design my own yurt and the local codes called for 20-85 psf for snow (for a 20' yurt, 3-13 tons...). Your 6" of heavy, wet snow on a 16' yurt works out to ~2800 lbs, or 80 lbs/roof pole, or 14 psf, assuming 45% water by volume & 35 roof poles.

From the modern yurts I've seen, they beef up the roof poles to high grade (2400 or so) 2x4 and reduce roof pole number (~30?) and use a much sparser lattice, relying on vertical studs on the wall in heavy snow. The

camping yurts

I've seen use a moderate number of roof poles (30-40 1x3") with a moderately spaced lattice and a relatively thin crown ring. The traditional mongolian yurts use a lot of roof poles (60+, 2x2) with much closer spaced lattice and a hefty crown ring, supported by bagana (effectively halving the roof span). All the weight going into the tension band/cable also goes through the crown ring, which is what worries me about a camping yurt with snow...

[Bob Rowlands]

If interested in details of a strong roof ring design featuring 1x3 rafters on edge, the ring I built is online.

Google here: Clan Yama Kaminari

Click on yurt build and scroll through the build until you get to the roof ring assembly. I modified mine by substituting solid 4x4 cut to correct dimension instead of the goofy beveled 1x on edge, because I reasoned a solid wood blocking is alot stronger design. More glue and screw area.

Also I widened the plywood width an inch. I can attest that ring is fantastically strong design. I used urethane construction adhesive and 3" plated screws during the assembly. I also primed and put two coats of Rustoleum enamel on it. If there's a bombproof 16' yurt roof ring, that one is it.

[Clean Air Yurts]

Hey everyone,
As far as

camping yurts

go, snow is certainly an issue. Snow is an issue with any building. Just look as Boston where building that have withstood 250 years are failing all over the city. My cousin had to shovel off his house 4 times already.

So unless you are planning on building a full-scale yurt with 2x4 rafters (for a smaller diameter) I would not count on having it winter-ready without planning on brushing off the snow every 3" at a time. Lighter yurts may stand up to the snow, but it is so unpredictable that you risk collapse from uneven loading unless it is strong enough to take anything that the weather can trow at it. Blowing snow can easily make a drift on one side that is much deeper than the average snowfall and cause collapse. Yurts are strong, but snow is always heavier.

The ring is one of the weak points to lightweight yurts. Our compression ring is a steam-bent hardwood ring that weighs in at 4-6 pounds. This make it super easy to carry, setup and store. It holds hundreds of pounds of weight, but will fail at higher or uneven loading. It can be strengthened with fiberglass at additional cost, but it is not necessary for a standard camping yurt for all use except in snow.

The issue with strength to weight is the main factor. All yurts can be made stronger with larger and heavier materials. No real news there. It shows the adaptability and the problems of the structure in the modern world.

Many people want yurts to use as a permanent space, or one that matches the comforts and use of real solid buildings. Yurts are tents, they are not buildings. They were designed to be portable and light weight. The Mongolians made them as light as they could, while still realizing that they would freeze to death if they let their yurt collapse in the winter. Now we can make yurts that are much lighter - our yurts are 50-200 pounds - because they are not our only homes. We can also make yurts that are so heavy that they will most likely never be moved - any large yurt with a platform and all of the modifications that are added.

As far as Brooklyn, we have setup a few of our yurts in backyards, or in small spaces. They are considered tents because they are lightweight and easy and fast to setup (30 min), but are not meant to be used all winter long in snowy climates. We would recommend one of our yurts that can be used when needed and are small enough to store in a closet during most of the winter or when you don't expect to use it for a week.

We did just find a new cover fabric with integrated

insulation

that should be way better than the reflective

insulation

at a full R10 as opposed to a theoretical reflective R-value. But it is a while away from production ready. We know about yurts in winter. I am sitting in one right now at it is -4F outside and the yurt has two layers of reflective insulation. It works, but not well compared to any standard house insulation. Certainly not as well as a crappy 2x4 wall with fiberglass insulation. That is the main issue we have with yurts, their energy efficiency.

Matt Rogers

Clean Air Yurts

www.cleanairyurts.com

[Jafo]

I think I might snowshoe up to my yurt tomorrow and fire up the wood stove. We have a couple feet here that should probably go. I have the snow kit with my pacific yurt with the 2X6 rafters.

[Bob Rowlands]

My 16' yurt is a simple nomadic style camping yurt designed by SCA participants for traveling to various events. It is lightweight and easily movable, just like the Mongolian yurts I have seen in YT videos.

In terms of snow load strength, how it measures up to any others I have no idea. I can attest it will withstand nearly a foot of moderately wet snow, without baganas. I'm so sure it will withstand such a load that I have no urge to go out and clear the roof of snow during a heavy snow fall here along the front range of CO. During a snow storm like the one that hammered the northeast U.S, I assuredly WOULD clear the roof however.

If I opted for a 20' - 6 meter- yurt I'd increase the strength by upping the cable to 1/4", enlarge the roof ring to accept 1x4 rafters, make it wider in diameter, use 5/4 plywood instead of 3/4, and install baganas. I'll bet I'd get a 6 meter camping yurt with no collapse issue. In fact, if I was a very young man considering living cheaply, I'd build that exact yurt.